The shoot and fruit borer, Leucinodes orbonalis (Lepidoptera: Crambidae) is the major cause of low productivity in eggplant and insecticides being the mainstay of management of L. orbonalis. However, field control failures are widespread due to the evolution of insecticide resistance. Taking advantage of the whole genome sequence information, the present study investigated the level of insecticide resistance and the expression pattern of individual carboxylesterase (CE) and glutathione S-transferases (GSTs) genes in various field collected populations of L. orbonalis. Dose-mortality bioassays revealed a very high level of resistance development against fenvalerate (48.2–160-fold), phosalone (94-534.6-fold), emamectin benzoate (7.2–55-fold), thiodicarb (9.64–22.7-fold), flubendiamide (187.4–303.0-fold), and chlorantraniliprole (1.6–8.6-fold) in field populations as compared to laboratory-reared susceptible iso-female colony (Lo-S). Over-production of detoxification enzymes viz., CE and GST were evident upon enzyme assays. Mining of the draft genome of L. orbonalis yielded large number of genes potentially belonging to the CE and GST gene families with known history of insecticide resistance in other insects. Subsequent RT-qPCR studies on relative contribution of individual genes revealed over-expression of numerous GSTs and few CEs in field populations, indicating their possible involvement of metabolic enzymes in insecticide resistance. The genomic information will facilitate the development of novel resistance management strategies against this pest.

Background: Association of several morphological traits such as trichome length and trichome density on the pod surface have been found to influence host plant resistance to insect pests. Genetic diversity analysis is used to identify the divergent genotypes and to utilize these genotypes to exploit heterosis. Further, morphological characters are stable across environments owing to oligogeneic nature, they serve as morphological markers in breeding which can be used in varietal or genotypic identification, varietal purification and even in seed production. Hence, the current study aimed to investigate on host plant resistance using portable paper microscope ‘foldscope’, genetic diversity and morphological characters.Methods: A total of 154 germplasm lines with three checks were evaluated in Augmented Block Design (ABD) at Zonal Agricultural Research Station (ZARS), Kalaburagi, during kharif, 2018 to study their genetic diversity. Trichome length and trichome density were recorded using ‘foldscope’ 75 randomly selected genotypes, then correlated with shrivelled seed yield per plot due to pod fly incidence. Morphological characterization of 14 qualitative traits were recorded.Result: Grouping of 157 germplasm lines into twelve clusters indicated a wider genetic diversity for the traits studied, of which 7 clusters were solitary with one entry each. The genotypes with more trichome density and length had less damage by the pod fly. Large variations for morphological characters was observed among the genotypes for qualitative traits such as pod colour, stem colour, flower colour, seed morphology and pod trichomes.

Abstract:The restorer lines are used to get fertile hybrids in hybrid seed production system of sunflower. Improvement of R-lines for fertility and oil content of sunflower is required to get desirable hybrids upon crossing. In the present study, 6 restorer lines were crossed in full diallele and both direct and reciprocal crosses along with parents were evaluated for their combining ability. The analysis of variance revealed higher magnitude of SCA variance than GCA variance for all the characters studied except for days to 50 per cent flowering. Among six parents, GMU-520 and R-GM-41 were best general combiner for plant height, head diameter, test weight and leaf size in the desired direction. However, GMU-520 has advantage of yield per plant and oil content. From 15 direct crosses R-GM-41 x R -GM-49 exhibited significant specific combining ability for viz., days to 50 per cent flowering (-1.08), plant height (13.69), head diameter (4.79), leaf size (0.74), yield per plant (17.14), volume weight (2.54), test weight (1.75) and oil content (0.34) followed by RCR-630 x GMU-520, R-GM-41 x EC-602060, R-GM-49 x GMU-520 and EC-602060 x GMU-520 each exhibiting good specific combining ability for majority of characters. Among reciprocal crosses R-GM -41 x RCR-8 exhibited a high reciprocal effects for head diameter (4.57), yield per plant (15.16), test weight (2.02) and leaf size (0.75).

The material for study of genotype x environment (G x E) interaction comprised of 23 genotypes, which were tested in four environments, during kharif-2012 and 2013 at two locations in Agricultural Research Station, Kalaburagi and Raddevadgi located in north eastern dry zone (Zone 2) of Karnataka. The experiment was laid out in lattice design with two replications. Highly significant differences among genotypes were observed for all the characters except number of pods per plant and yield per plant. Environmental +(Genotype x Environment) interaction was significant for days to 50 per cent flowering, day to maturity, plant height, pod bearing length, number of pods per plant and seed yield per plant. The variance due to pooled deviation was highly significant for all the characters which reflect the presence of sufficient genetic variability in the material. Stability parameters for seed yield per plant indicated that ASHA(ch) was stable and desirable, followed by RVK-275 and GRG-811 which were specifically adopted for favourable and poor environments respectively. Two years of field screening for Fusarium wilt (FW) and Sterility Mosaic Disease (SMD) yielded three genotypes viz., GRG-811, GRG-2009 and ASHA for resistance to Fusarium wilt and moderate resistance to SMD. Hence, these genotypes can be used directly as a variety or choice of parent for hybridization programme.

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The increase in food production is greatly contributed by green revolution, thereby leading to reduction in people's starvation. However, this caused greater depletion of micronutrient reserve in soil and thereby accentuated wide spread deficiencies of micronutrients in crop species. Hence, biofortification program has been initiated to identify varieties having high iron and zinc along with high yield. In the present study 46 rice genotypes along with 4 checks were received from Indian Institute of Rice Research (IIRR), Hyderabad, India and were evaluated for yield and yield attributing traits, grain quality parameters and estimation of micronutrients.For yield and yield attributing characters most of the traits showed high heritability associated with high genetic advance indicating fixation of genes and presence of additive gene action in these traits. The results obtained by micronutrient estimation revealed that iron and zinc contents of dehusked grains differed significantly between the genotypes. Among various studied genotypes the promising genotypes with highest grain iron and zinc content along with higher yields and with intermediate amylose content were identified. These promising genotypes identified can be released to farmers after testing in multilocation trials for their stable performance or they can be used as parents in hybridization programme.

The present investigation was carried out during kharif 2012 at the Agricultural Research Station, Gulbarga and other four locations located in north eastern dry zone (Zone 2) of Karnataka, to know the stability of the nineteen advanced genotypes of pigeonpea. Highly significant differences among genotypes were observed for all the characters except number of pods per plant, number of seeds per pod and seed yield per plant. The variance due to Genotype x Environment found significant for the characters like days to 80% pod maturity and number of seeds per pod. Environment (linear) interaction component was significant for all the traits. The variance due to pooled deviation (non-linear) was highly significant for all the characters except for number of seeds per pod which reflect considerable genetic diversity in the material. Out of 19 genotypes studied two entries viz., GRG-109 and GRG-107 were consistent and high yielding compared to local checks.

Context Broadening the gene pool of staple food crops by incorporating desirable genes from wild/relative species is way to achieve higher genetic gains. The African rice species Oryza glaberrima Steud. is a source of genes for genetic improvement of Oryza sativa L. to various biotic and abiotic stresses. Aim The study was undertaken to identify genomic regions associated with yield and yield-related traits in interspecific backcross mapping populations derived from variety IR64 (O. sativa indica) × O. glaberrima. Methods The BC1F2 and BC1F2:3 populations were phenotyped for days to 50% flowering, plant height, number of tillers, number of productive tillers, panicle length, spikelet fertility and grain yield under irrigated conditions. The BC1F2 population was genotyped with 99 genome-wide polymorphic SSR markers. Quantitative trait loci (QTLs) associated with yield-enhancing traits were identified through single marker analysis. Key results Significant genetic variability was observed with moderate to high heritability in mapping populations. Genotyping revealed the presence of segregation distortion and skewed genome composition. Single marker analysis identified 20 QTLs linked to the studied traits. A QTL linked to grain yield, qGY-4.1, derived from O. glaberrima was found in both populations with high phenotypic variance. The chromosome region around marker RM510 was identified as a QTL hotspot and putative candidate genes were identified. Conclusions Our study demonstrates that O. glaberrima can serve as a valuable genetic resource for genetic improvement of yield-enhancing traits in O. sativa cultivars. Implications The identified QTLs regions can be employed in molecular breeding. The promising introgression lines identified can be used as pre-breeding lines in future breeding programs.